The present invention relates generally to a mowing apparatus of the reciprocating sickle type and more particularly to double sickle cutterbar with improved operational characteristics.
The general construction and mode of operation of reciprocating sickle cutterbar mowing apparatus is well known, as is the importance of making a smooth and sharp cut of crop material across the full width of the swath being harvested. In a continuing process, the trend in agricultural harvesting machine design has been to develop larger machines that result in increased operational efficiency. This trend has resulted not only in larger and wider harvesters, but also increased ground speed, particularly in the design of combines, forage harvesters and windrowers.
These machines typically employ a sickle cutterbar as the means for severing the crop material from the ground. It has been, however, discovered is that by increasing the width of cut of a sickle cutterbar, problems arise because the increased length and speeds are opposed by a practical limit of the energy that can be alternatively applied to and extracted from individual reciprocating sickle assemblies, since the longer sickle assemblies and the higher operating speeds increase this energy transfer to the point where supporting forces become excessively amplified and destructive vibrations are generated.
One successful approach to alleviating this problem was to make the sickle cutterbar in two separately driven pieces, partially overlapping to prevent leaving a strip of uncut crop materials. This approach is shown and described, for example, in more detail in U.S. Pat. Nos. 3,577,716 and 5,024,051. The structures shown in the patents identified immediately above, and other similar structures, have seen several improvements through the years; however, current similar structures still exhibit disadvantages in design that make them difficult to set up and adjust, and that cause them to xe2x80x9ccatchxe2x80x9d crop material during operation and thereby interrupt the smooth flow of cut crop material rearwardly for conditioning or further treatment.
It would be quite advantageous to have a double sickle cutterbar that overcomes the problems mentioned above.
Accordingly, it is an object of the present invention to provide a sickle cutterbar assembly that is easy to set up and adjust.
Another object of the present invention is to provide a sickle cutterbar assembly that minimizes the interference to the flow of cut crop material rearwardly in the header.
It is another object of the instant invention to provide a double sickle cutterbar assembly that uses an improved hold-down design to reduce the xe2x80x9ccatchingxe2x80x9d of cut crop material.
It is yet another object of this invention to provide an improved sickle cutterbar assembly that is durable in construction, inexpensive of manufacture, carefree of maintenance, facile in assemblage, and simple and effective to set up, adjust and use.
These and other objects are attained by providing an improved double sickle cutterbar assembly using sickle bar hold-downs of improved design and other improved assembly elements that result in significantly reduced xe2x80x9ccatchingxe2x80x9d of cut crop material and thus improved feeding from the cutterbar to other operational elements of the header/harvester.